Cant authenticate as a user with Postman (400 error)

I posted this as a reply in another thred while it should have been a new post, sorry!

So I am trying to use the PBI API via REST requests done by Postman. All of these requests will be done by a service account with a PowerBI Pro license (currently my account for testing purposes) which will copy/modify workspaces so that we can automate the workspace creation process.

I know the credentials are working because I can log with them on the PowerBI website and I can make API calls using a Python API library (which unfortunately does not have all the required end points, hence me using Postman).

Re: Cant authenticate as a user with Postman (400 error)

Sorry, no solution here. But I am having the same issue since over half a year. Only the C# demo of MS seemed to work, nothing else. Would love to hear of someone getting the Token API working in Postman.

Re: Cant authenticate as a user with Postman (400 error)

I managed to make it work by asking my azure sysadmin to create a service account and making this account the owner of the app. I dont understand why it would make it different than using my own credentials (with me as owner) but apparently, it does because now I can log via password...

Re: Cant authenticate as a user with Postman (400 error)

Do you maybe have some more detailed informations regarding that service account and how it is created? I would like to ask my Azure Admin too for that, but might have to point in the right direction. Thanks!

Re: Cant authenticate as a user with Postman (400 error)

AFAIK, the sysadmin registered the powerbi app, then created a normal user and assigning the user as the owner of the registered PowerBI app, and also granting the permission to the app (something I was not able to do when I was the one registering the app).